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Results for “Al-Hf-N”

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Hf5Al3N by Materials Project

Hf5Al3N crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 6-coordinate geometry to two equivalent Hf and six equivalent Al atoms. Both Hf–Hf bond lengths are 2.83 Å. All Hf–Al bond lengths are 2.84 Å. In the second Hf site, Hf is bonded in a 2-coordinate geometry to five equivalent Al and two equivalent N atoms. There are a spread of Hf–Al bond distances ranging from 2.83–3.18 Å. Both Hf–N bond lengths are 2.30 Å. Al is bonded in a 9-coordinate geometry to nine Hf atoms. N is bonded to six equivalent Hf atoms to form face-sharing NHf6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3AlN by Materials Project

Hf3AlN crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a distorted L-shaped geometry to three equivalent Al and two equivalent N atoms. There are two shorter (2.86 Å) and one longer (2.94 Å) Hf–Al bond lengths. Both Hf–N bond lengths are 2.24 Å. In the second Hf site, Hf is bonded in a distorted bent 150 degrees geometry to two equivalent Al and two equivalent N atoms. Both Hf–Al bond lengths are 2.86 Å. Both Hf–N bond lengths are 2.28 Å. Al is bonded in a 9-coordinate geometry to eight Hf atoms. N is bonded to six Hf atoms to form a mixture of edge and corner-sharing NHf6 octahedra. The corner-sharing octahedral tilt angles are 25°.

36 MATERIALS SCIENCE↗